A puck (mass m₁ = 0.50 kg) slides on a friction less table as shown in Figure P9.39. The puck is tied to a string that runs through a hole in the table and is attached to a mass m₂ = 1.5 kg. The mass m₂ is initially at height h = 1.5 m above the floor with the puck traveling in a circle of radius r = 0.40 m with a speed of 1.5 m/s. The force of gravity then causes mass m₂ to move downward a distance 0.15 m.?

(a) What is the new speed of the puck??

(b) What is the change in the kinetic energy of the puck?

Concerned with the magnitude of the angular momentum, not its sign.

Figure P9.39

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